// 8bits -> 1bytes -> kb -> mb -> g -> T
let a = 0b10010; //二进制
console.log(a);
let b = 0o122; //八进制
console.log(b);
let c = 0x14;
console.log(c);
console.log(parseInt('0x155',16));
//任意进制转换 toString()
let d = 78
console.log(d.toString(2));
//ASCII GB2312 

console.log('A'.charCodeAt());
console.log('a'.charCodeAt());
console.log('z'.charCodeAt());
console.log('Z'.charCodeAt());
// < = 127 英文字符 >127汉子 第一个字符  utf-8
//GBK GB18030
//unicode utf
